Lily Multiplication by seed

The sense of achievement and pride obtained by raising lilies from seed is far greater than that given by vegetative reproduction from bulbs. This is only natural, for even if lilies raised from seed do not always ‘come true’, they quickly make up for what they lose in beauty by numbers and vigorous growth. If a garden is to be fdled with lilies, raising them from seed is certainly the least expensive method and, given a little luck, some of the new plants will excel the mother plant in every respect. Growing lilies from seed is not complicated, provided particularly difficult varieties are not chosen; but patience is certainly needed, as it is usually three years before efforts are rewarded with blooms!

Growing plants from seed has two advantages. Firstly, virus disease cannot be transmitted to the new plant as is the case with vegetative reproduction. Secondly, home-grown bulbs can be planted out immediately and, unlike bought ones, their root growth is intact; in addition, they need not be kept out of the soil for any length of time.

Germination categories

Before sowing lily seed it is necessary to establish to which of the four different groups, all different in their mode of emergence, a particular variety belongs. Seedlings belonging to the first group emerge above ground (epigeal), from between two to six weeks after sowing (1mmediate cpigeal), or after several months (delayed epigeal). Seeds which germinate from below ground level, without producing a cotyledonf fall into the second group (hypogcal) and are similarly subdivided into immediate hypogeal and, in the case where germination can take up to one year, delayed hypogcal. 1. Immediate epigeal

Most of the trumpet lilies and the Asiatic Maculatum, Davidii and

Tigrinum groups fall into this category; individually they are as follows:

Amabile

Bakerianum

Callosum

Ccrnuum

Concolor

Dauricum

Davidii

Duchartrei

Formosanum

Lankongense

Leichtlinii Var. Maximowiczii

Leucanthum Var. Chloraster

Longiflorum

Neilgherrense

Ncpalense

Nobilissimum

Papilliferum

Philadelphicum

Philippinensc

Primulinum

Pumilum

Regale

Sargentiae

Speciosum Var. Gloriosoides

Sulphureum

Taliense

Tigrinum

Wallichianum

Tigrinum Hybrids

Trumpet Lily Hybrids

Wardii

Wihonii

Aurelian Hybrids

Cernuum Hybrids

Davidii Hybrids

Midcentury Hybrids

After a four-t0-six-wcek incubation period, the embryo produces a downward-growing root – a little thicker in one part than elsewhere -from which the future bulb grows. Finally the upward-growing, loop-shaped shoot, full of chlorophyll, pushes the seed case through the soil until the cotyledon stands erect. The first true leaf emerges approximately four weeks later. 2. Delayed epigeal

Sowings of freshly harvested seeds of lilies in this group often give the same quick results as varieties in Group I. candidum carniolicum chalcedonicum henryi kucanthum pomponium pyrenaicum sargentiae

Although embryo development is exactly the same, seeds may take one year (often two years in the case of L. carniolicum) before they germinate. Seeds of L. candidum germinate unevenly, and can take as little as four weeks or as long as two years. Harvest-fresh seeds of L. henryi germinate immediately, but if the seeds are brown and dry, germination is usually delayed. 3. Immediate hypogeal

This is the smallest of the four groups, and consists of the following varieties and hybrids:

Brownii Var. Australe

Dauricum

Martagon Var. Album

Parryi

Philadelphicum Speciosum

Golden Chalice Hybrids

After being subjected to a temperature of 68-77 deg F (20-25 deg C), the root emerges from the seed and produces a small bulb. After a short rest-period, the first true leaf pushes through the soil without any cotyledon having appeared. 4. Delayed hypogeal

Martagon, Japanese, and nearly all North American lilies belong to this group:

Alexandrae

Auratum

Bolanderi

Brownii

Bulbiferum

Canadense

Columbianum

Distichum

Grayi

Hansonii

Humboldtii

Japonicum

Kelloggii

Maritimum

Martagon

Michiganense

Monadelphum

Nevadensc

Occident Ale

Pardalinum

Paruum

Philadelphicum

Polyphyllum

Rubellum

Rubescens

Speciosum

Superbum

Tsingtauense

Washingtonianum

Auratum-Spcciosum Hybrids

Bellingham Hybrids

Martagon Hybrids

The mode of lily-seed germination is suited to the life-cycle of the plant and depends on the climate of its native habitat. Wild L. martagon drops its seed onto the warm soil at the beginning of September and produces embryos below ground. The small embryos withstand low winter temperatures, snow, and ice, and produce their first leaf immediately the soil becomes a little warmer during the following spring. If the seed is saved and not used for immediate sowing, the vital autumn seed-germination and bulb-production periods are missed, and if sowing is delayed still further the temperatures become, in any case, too low. L. miratum seeds ripen too late to be germinated during autumn, and it is impossible to produce bulbs until the following spring; the first leaf cannot therefore emerge until another 12 months have passed – that is, during the subsequent spring – because the underground bulblets must first pass through a cold period to stimulate leaf formation.

It is essential always to remember the lily’s natural life-cycle when sowing seed of lilies in this group. It does not matter if the seed of lilies in this group is sown during late autumn or in the spring, as germination and leaf production cannot take place in the following summer but only during the subsequent one.

Delayed hypogeal: Warm and cold treatment

The Americans have shown that the germination period and the growing cycle can be shortened if the warm conditions in which seeds are normally kept for three to six months are interrupted by a brief period of cold storage. Breeders, nurserymen, and gardeners have welcomed the system, and use it widely.

When dealing with Group 4 lilies, the most practical method of propagation is to use jam-jars or large preserving jars, preferably the type with screw-top lids. Seeds, first dusted with fungicide, are placed in ajar together with the previously sterilized and lightly damped growing medium, which can be either peat, sphagnum moss, vcrmiculite, or perlitc. The jar is sealed with cither the screw cap or a piece of securely tied polythene or foil, before being stored in a temperature of 59-70 DEG F (15-21 deg C); American West coast lilies only require 50-59 DEG F (10-15 DEG C). Three to six months later the root, mostly with a tiny bulb, pushes through the seed case; this is the signal for the cool-storage period to begin. A refrigerator kept at 36-39F (2-4 deg C), or a cellar or other suitable cool place up to 46 deg F (8 deg C), provide the best conditions for the following two to three months, after which the seedlings are planted out into warm quarters and produce their first leaf within two to four weeks. The timetable works out very well in practice; the freshly harvested seeds are put into warm storage during October, November and December; the cold storage period occupies January, February and March; then the seedlings are ready for planting out just as spring is about to commence, and have ample opportunity to develop with the whole of the summer before them. The timetable is, of course, subject to variation, depending on whether new or old seed is used, if cold storage takes place in a refrigerator or cellar, and also on the particular variety. Newly sown seed of L. auratum can be obstinate, and some may lie dormant for a long time; remarkable, too, is their uneven habit of germination with some seed germinating either long before or long after the main bulk. This is not necessarily a disadvantage; it is perhaps even one of nature’s protective devices, for if circumstances suddenly turn unfavourable for the germination of the variety, not all seedlings will be destroyed. Breeders usually segregate the early-emerging seedlings for use in breeding in the hope that this trait can be genetically fixed.

If glass jars are not used, boxes, pots, or even polythene bags make alternative containers, though they lack the versatility and transparency of glass, which aids accurate control. As in the case of bulb-scale multiplication, it is important that the growing medium should be only slightly damp, never really wet, and that it should be sterilized before use.

The fortunate gardeners of the United States are able to buy already germinated lily seeds for immediate planting in their gardens, but usually only of the Auratum and Speciosum types.

Sowing seeds

Seeds are obtained from home-grown plants or through exchange or purehase.

As soon as the seed capsules open, they are carefully removed from the plant and dried in a warm room. The 200-500 seeds are later put into a bowl. Unsuitable seeds are not as heavy as the others, and consequently are easily separated from those containing an embryo (a dark nucleus in the centre of the seed) by blowing lightly into the bowl.

Old seeds often give only poor results. In general, lily seeds stored in a warm room retain their germination for only two years, after which time it drops to nil. If seeds, after being dried in a desiccator over a drying agent, are stored in an airtight container at room temperature, they remain viable for five years, and 30 per cent of them even germinate after seven years. Still better results are obtained if, after desiccation, the airtight jam-jars can be stored at a temperature of 41 deg F (5 DEG C); an experiment with L. regale seed so treated and stored has confirmed that, even after 15 years’ storage, 93 per cent of the seeds remain viable.

The seed, like bulb scales, should be treated with a fungicide before being sown; to apply the dressing, both seed and the prescribed amount of fungicide are put into a tin, and shaken well until the seeds are completely coated.

Sowing in the open

For optimum results, it is advisable to sow only the quick-germinating seeds of lilies in Group 1 in the open, and then only between the end of March and mid-May. The seed bed must not be too firm, and should preferably consist of light soil rich in humus which, if necessary, can be improved with a peat dressing. If the soil is not in very good condition, an application of low-nitrogen fertilizer will prove beneficial, provided it is worked well into the ground. Seeds should be sown 2/5-3/5 inch deep, 2/5 inch apart with 6-10 inches between rows, and watered immediately with a fine spray. Never allow the seed bed to dry out.

To keep seedlings growing after they have germinated, applications of 0-3 per cent solution of a liquid fertilizer every two weeks are beneficial. Of particular importance is the scrupulous removal of weeds as soon as they show; if they are not removed at once, there is every likelihood that the small, newly formed lily bulbs will be loosened or, worse still, pulled out together with the weeds.

The young plants also appreciate a mulch of either peat or sawdust during the winter months. This also avoids the possibility of their being lifted out of the ground by alternate frost and thaw. Mulching materials such as leaves, grass-cuttings and straw provide too dense a cover, and are best avoided.

Seedlings ought ideally to be left in their original beds until the autumn of the second year or the spring of the third year, when they can be safely transplanted to their permanent positions. Occasionally, one of the seedlings in the quick-germinating group provides a pleasant surprise, and flowers as early as the second year.

Unfortunately, open sowings usually suffer from heavy seedling losses, through a variety of causes – weed competition, flooding as a result of heavy rains and thunderstorms, and bad overwintering during the first year. Open sowing perhaps has advantages in maritime climates, but is hardly to be recommended in a continental climate subject to dry summers and sharply alternating frost and thaw conditions.

Sowing under glass

Notably better results are obtained if seeds can be raised in a coldframe. Good weather permits sowing as early as the end of February, seeds germinate more quickly, seedlings develop better and remain protected through the winter months. Ventilation and the provision of shade during sunny weather are, of course, important.

Even earlier sowings are possible if seed-boxes or pots are stored in a veranda, on a window-sill or anywhere in a heated room, provided sufficient light is available. When the weather turns warmer, the seed containers are transferred to a coldframe.

If a greenhouse is available it, of course, provides all these advantages and more. Sowings can be brought forward to January, management is more efficient, weather has less influence, and pests and disease are easier to control. Rare and difficult seeds or precious seed from first crosses are more safely raised in a greenhouse than anywhere else.

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